Patent Document 1 discloses a conventional cutting tool. That is, such cutting tool is a cutting tool which comprises a corner part and in which a cutting edge member containing an ultrahigh-pressure sintered body, being comprised of at least either cubic boron nitride or diamond, is secured to an area containing the corner part, and a chip breaker having a breaker wall surface is formed in a surface of the cutting edge member. A recessed part is formed between two adjacent breaker wall surfaces. The cutting tool employs a cutting insert, and the cutting edge member is secured to the cutting insert.